Correlation of the Week (in the wild)

The New York Times printed an article today about how important statistics were in the real world which I mentioned in a previous blog post. One of the last paragraphs offers a great example of correlation versus causation which has now won the SITW Correlation of the Week! Congratulations 1940s public health experts.

“The rich lode of Web data, experts warn, has its perils. Its sheer volume can easily overwhelm statistical models. Statisticians also caution that strong correlations of data do not necessarily prove a cause-and-effect link.

For example, in the late 1940s, before there was a polio vaccine, public health experts in America noted that polio cases increased in step with the consumption of ice cream and soft drinks, according to David Alan Grier, a historian and statistician at George Washington University. Eliminating such treats was even recommended as part of an anti-polio diet. It turned out that polio outbreaks were most common in the hot months of summer, when people naturally ate more ice cream, showing only an association, Mr. Grier said.” – David Alan Grier, NY Times Article

Some notes: 1.) Whoops. 2.) If you’re name is David Alan Grier, and you’re not this David Alan Grier, go by David Grier. Just drop the Alan.